Deformation behavior of nanoparticle/fiber-reinforced nanocrystalline Al-matrix composites

Deformation behavior of nanocrystalline (nc) Al-matrix composites reinforced by nanoparticles/carbon nanotubes (CNTs) has been studied under quasi-static deformation conditions at room temperature. The nc composites are fabricated by hot-extrusion of the mechanically milled nc powders containing randomly embedded nanoparticles/CNTs in the matrix. The nc composite reinforced with 0.7 vol.% CNTs can reach a strength of 480 MPa with elongation to failure of 8% under tension through the resistance of the growing necks formed just after yielding. The nc composite reinforced by CNTs/nanoparticles shows 610 MPa in yield strength. The tightly bonded interface between the matrix and CNTs can also effectively transfer the load to the fibers. Further enhanced strength can be achieved by reinforcing the matrix with dispersed nanoparticles in such composites.